Small Yami problem

[brew1891]

I have a 1989 Yamaha 15hp tiller motor. It is manual start and no power. Recently i noticed that some exhaust seemed to be exiting where the lower unit joins the main shaft. it seemed to be a very small pinhole on the side facing away from the tiller handle. Yesterday i noticed there is some black oil pooling in this area like its coming out from the inside. I tried to tighten up the lower unit bolts but they seemed tight. Any suggestions as to what the problem is? Do i just need a new lower unit seal? is this a sign of larger problems?

Thanks!

 

[deejaycee_2000]

Re: Small Yami problem

welcome to iboats ..... do you have a pic? ...... sounds to me like it could be either the drain hole on the side or your tell-tale, that's not pumping water ........

 

[brew1891]

Re: Small Yami problem

i will work on getting pic up

 

[brew1891]

Re: Small Yami problem

Here are some pics of the problem:

Thanks!

 

[lifeisfun]

Re: Small Yami problem

Wow, very nice pictures !

 

[Ray Neudecker]

Re: Small Yami problem

Looks to be coming from the powerhead. Check for a fuel leak or carb with needle stuck first.

 

[brew1891]

Re: Small Yami problem

I just replaced the fuel diapragms on the outside of the carb. No fuel came out when i opened it, i always unplug the gas line when flushing the motor so all the gas runs out of the system.

Would the excess fuel be visible in the bottom of the cowling area? or would this be an internal problem...i.e. can't be seen from outside the engine?

Also before this problem the engine was having some problems keeping fuel at high rpms until it got really warm but a new Yami fuel line seemed to help and the problem seemed to just pass...could this be related?

Thanks for the help so far...if i could find a used 18hp 2 stroke tohatsu i'd probably just buy that but they seem to be rare.

 

[brew1891]

Re: Small Yami problem

Wow, very nice pictures !

macro mode...helps a lot for close ups...its actually my older "fishing" digital camera

 

[boashna]

Re: Small Yami problem

when ever an engine does not start go to basics first , are you getting fuel , are you getting spark , weather you need a lower unit or not is not an issue yet. you can have running engine with bad transmission . lets start the engine first. take the spark plugs out to make it easier to pull start and see the piston. buy a can of engine starter to make your job easier spray and pull. clogged carburetor or fuel line is what I go after . on my Suzuki the area in question is sealed by silicon and it appears that you have a exhaust leak and since you mix fuel and oil, you have a residue of oil in the area . when you change your impeller , you can fix the leak also. your old fuel line had a leak and needed it to be replaced .

 

[boashna]

Re: Small Yami problem

to fix your impeller

www.thehulltruth.com/forums/thread-view.asp?tid=79469&start=1

www.2coolfishing.com/ttmbforum/showthread.php?t=50890

above are two good leads with pics .

 

[boashna]

Re: Small Yami problem


www.thehulltruth.com/forums/thread-view.asp?tid=79469&start=1

www.2coolfishing.com/ttmbforum/showthread.php?t=50890

above are two good leads with pics .

 

[deejaycee_2000]

Re: Small Yami problem

ok now this makes much more sense, seems like someone had a bit of difficulty removing the lower unit and damaging it quite a bit ...... you will need to take if off and install new seals ..... and for the rest read above .......

 

[brew1891]

Re: Small Yami problem

thanks for the help

the motor starts up great...its just needs to warm up a lot or it will die at full throttle...i think it was either the fuel diapraghms or it needs a carb rebuild.

the exhaust leak theory does make sense becuase it was puffing out exhaust and now residual oil/gas is seeping out. Ok sounds good to me!

 

[cbsykes]

Re: Small Yami problem

I too have a black/brown milky-ish residue that smells like exhaust exiting the same area on my Yamaha 25. It sticks up there after a while and I usually just wipe it off. Mine is a 2005 and has been doing it since it was new. I have been told that it is normal...is this true?